The present invention relates to a mister nozzle and especially to a mister nozzle having a check valve incorporated therein to shut off the water passing through the misting nozzle to prevent draining of the water from the mister water supply pipes.
In a typical nursery propagation house, mist nozzles are suspended above the plants on polymer tubing. Water is supplied to these nozzles through polymer tubes from an overhead system of pipes and valves. A valve must be positioned between each mister and the polymer tubing which is shut off to prevent the whole system from draining out through the nozzles when the water is turned off. When the water supply is turned on, pressure builds to a point overriding a check valve so that the valve opens. When the water supply is turned off, the pressure in the system drops so that the check valve is closed to prevent the water from draining out the mister nozzles. When the system pressure drops to a point equal to or less than the check valve seal force, the valve shuts and traps the remaining water in the system. Prior check valves have been separate products consisting of several parts. A check valve is vented through small vent holes that connect the vented side of the check valve seal to atmosphere through the side of the valve. The mister is a separate component having several parts which is attached to the bottom of a check or other valve hanging on the end of each polymer tube in the nursery propagation house.
Prior U.S. patents that involve water misting may be seen in the Corrigan U.S. Pat. No. 4,882,189 for a method of spraying water mist onto produce in a display case. Water is delivered to the nozzles by an upwardly extending supply pipe within the case, eliminating the need for an overhead mounting structure. The Hayman, Jr. et al. U.S. Pat. No. 4,914,339 is a misting system constructed of plastic pipe which is drilled and threaded to receive nozzle assemblies. Each nozzle has a valve that does not bleed to atmosphere so it requires another valve to lower the system pressure after the water supply is turned off. The Marcus U.S. Pat. No. 5,330,104 is a portable outdoor mister for providing a comfortable region within a relatively hot, dry environment and has a reservoir of water and a pump to supply the water for the spray. The Wintering et al. U.S. Pat. No. 5,441,202 is a misting system with improved couplers. This system has an automatic drain valve which includes a check valve operating in the reverse direction and can be positioned anywhere in the system by replacing a nozzle with the drain. The Jones U.S. Pat. No. 6,651,901 is a misting system nozzle holder with a manual slide shutoff valve. The misting system valve assembly is connected to a pressurized fluid supply.
The present invention advantageously combines a nursery mister with a check valve, eliminating a number of the components of a separate check valve and mister nozzle and, advantageously, vents the mister check valve to atmosphere downstream of the flow metering port and through the nozzle itself, allowing the incorporation of the check valve and a mister into one compact unit with the check valve located inside the mist nozzle housing downstream of the inlet port and upstream of the nozzle outlet.